Guang Xu, Jinhui Xu. An Improved Approximation Algorithm for Uncapacitated Facility Location Problem with Penalties. In Lusheng Wang, editor, Computing and Combinatorics, 11th Annual International Conference, COCOON 2005, Kunming, China, August 16-29, 2005, Proceedings. Volume 3595 of Lecture Notes in Computer Science, pages 644-653, Springer, 2005. [doi]
Abstract is missing.